feat: selection box

1 files changed, 195 insertions, 0 deletions

diff --git a/apps/web/src/hooks/use-selection-box.ts b/apps/web/src/hooks/use-selection-box.ts
new file mode 100644
index 00000000..4caecf17
--- /dev/null
+++ b/apps/web/src/hooks/use-selection-box.ts
@@ -0,0 +1,195 @@
+import { useState, useEffect, useCallback } from "react";

+

+interface UseSelectionBoxProps {

+  containerRef: React.RefObject<HTMLElement>;

+  playheadRef?: React.RefObject<HTMLElement>;

+  onSelectionComplete: (

+    elements: { trackId: string; elementId: string }[]

+  ) => void;

+  isEnabled?: boolean;

+}

+

+interface SelectionBoxState {

+  startPos: { x: number; y: number };

+  currentPos: { x: number; y: number };

+  isActive: boolean;

+}

+

+export function useSelectionBox({

+  containerRef,

+  playheadRef,

+  onSelectionComplete,

+  isEnabled = true,

+}: UseSelectionBoxProps) {

+  const [selectionBox, setSelectionBox] = useState<SelectionBoxState | null>(

+    null

+  );

+  const [justFinishedSelecting, setJustFinishedSelecting] = useState(false);

+

+  // Mouse down handler to start selection

+  const handleMouseDown = useCallback(

+    (e: React.MouseEvent) => {

+      if (!isEnabled) return;

+

+      // Only start selection on empty space clicks

+      if ((e.target as HTMLElement).closest(".timeline-element")) {

+        return;

+      }

+      if (playheadRef?.current?.contains(e.target as Node)) {

+        return;

+      }

+      if ((e.target as HTMLElement).closest("[data-track-labels]")) {

+        return;

+      }

+

+      setSelectionBox({

+        startPos: { x: e.clientX, y: e.clientY },

+        currentPos: { x: e.clientX, y: e.clientY },

+        isActive: false, // Will become active when mouse moves

+      });

+    },

+    [isEnabled, playheadRef]

+  );

+

+  // Function to select elements within the selection box

+  const selectElementsInBox = useCallback(

+    (startPos: { x: number; y: number }, endPos: { x: number; y: number }) => {

+      if (!containerRef.current) return;

+

+      const container = containerRef.current;

+      const containerRect = container.getBoundingClientRect();

+

+      // Calculate selection rectangle in container coordinates

+      const startX = startPos.x - containerRect.left;

+      const startY = startPos.y - containerRect.top;

+      const endX = endPos.x - containerRect.left;

+      const endY = endPos.y - containerRect.top;

+

+      const selectionRect = {

+        left: Math.min(startX, endX),

+        top: Math.min(startY, endY),

+        right: Math.max(startX, endX),

+        bottom: Math.max(startY, endY),

+      };

+

+      // Find all timeline elements within the selection rectangle

+      const timelineElements = container.querySelectorAll(".timeline-element");

+

+      const selectedElements: { trackId: string; elementId: string }[] = [];

+

+      timelineElements.forEach((element) => {

+        const elementRect = element.getBoundingClientRect();

+        // Use absolute coordinates for more accurate intersection detection

+        const elementAbsolute = {

+          left: elementRect.left,

+          top: elementRect.top,

+          right: elementRect.right,

+          bottom: elementRect.bottom,

+        };

+

+        const selectionAbsolute = {

+          left: startPos.x,

+          top: startPos.y,

+          right: endPos.x,

+          bottom: endPos.y,

+        };

+

+        // Normalize selection rectangle (handle dragging in any direction)

+        const normalizedSelection = {

+          left: Math.min(selectionAbsolute.left, selectionAbsolute.right),

+          top: Math.min(selectionAbsolute.top, selectionAbsolute.bottom),

+          right: Math.max(selectionAbsolute.left, selectionAbsolute.right),

+          bottom: Math.max(selectionAbsolute.top, selectionAbsolute.bottom),

+        };

+

+        const elementId = element.getAttribute("data-element-id");

+        const trackId = element.getAttribute("data-track-id");

+

+        // Check if element intersects with selection rectangle (any overlap)

+        // Using absolute coordinates for more precise detection

+        const intersects = !(

+          elementAbsolute.right < normalizedSelection.left ||

+          elementAbsolute.left > normalizedSelection.right ||

+          elementAbsolute.bottom < normalizedSelection.top ||

+          elementAbsolute.top > normalizedSelection.bottom

+        );

+

+        if (intersects && elementId && trackId) {

+          selectedElements.push({ trackId, elementId });

+        }

+      });

+

+      // Always call the callback - with elements or empty array to clear selection

+      console.log(

+        JSON.stringify({ selectElementsInBox: selectedElements.length })

+      );

+      onSelectionComplete(selectedElements);

+    },

+    [containerRef, onSelectionComplete]

+  );

+

+  // Effect to track selection box movement

+  useEffect(() => {

+    if (!selectionBox) return;

+

+    const handleMouseMove = (e: MouseEvent) => {

+      const deltaX = Math.abs(e.clientX - selectionBox.startPos.x);

+      const deltaY = Math.abs(e.clientY - selectionBox.startPos.y);

+

+      // Start selection if mouse moved more than 5px

+      const shouldActivate = deltaX > 5 || deltaY > 5;

+

+      const newSelectionBox = {

+        ...selectionBox,

+        currentPos: { x: e.clientX, y: e.clientY },

+        isActive: shouldActivate || selectionBox.isActive,

+      };

+

+      setSelectionBox(newSelectionBox);

+

+      // Real-time visual feedback: update selection as we drag

+      if (newSelectionBox.isActive) {

+        selectElementsInBox(

+          newSelectionBox.startPos,

+          newSelectionBox.currentPos

+        );

+      }

+    };

+

+    const handleMouseUp = () => {

+      console.log(

+        JSON.stringify({ mouseUp: { wasActive: selectionBox?.isActive } })

+      );

+

+      // If we had an active selection, mark that we just finished selecting

+      if (selectionBox?.isActive) {

+        console.log(JSON.stringify({ settingJustFinishedSelecting: true }));

+        setJustFinishedSelecting(true);

+        // Clear the flag after a short delay to allow click events to check it

+        setTimeout(() => {

+          console.log(JSON.stringify({ clearingJustFinishedSelecting: true }));

+          setJustFinishedSelecting(false);

+        }, 50);

+      }

+

+      // Don't call selectElementsInBox again - real-time selection already handled it

+      // Just clean up the selection box visual

+      setSelectionBox(null);

+    };

+

+    window.addEventListener("mousemove", handleMouseMove);

+    window.addEventListener("mouseup", handleMouseUp);

+

+    return () => {

+      window.removeEventListener("mousemove", handleMouseMove);

+      window.removeEventListener("mouseup", handleMouseUp);

+    };

+  }, [selectionBox, selectElementsInBox]);

+

+  return {

+    selectionBox,

+    handleMouseDown,

+    isSelecting: selectionBox?.isActive || false,

+    justFinishedSelecting,

+  };

+}